Title:
METHOD AND APPARATUS FOR TUFTING UNIFORM CUT PILE
Document Type and Number:
United States Patent 3730115
Abstract:
A tufting looper mechanism including a looper element or hook, a spreader element fixed proximate to the bill of the hook for receiving a tufted loop thereover, in a spread position, and a knife member, and means for reciprocably moving the looper element and knife member so that the knife member moves between the hook and spreader element to cut a spread loop held by the hook and spreader element in substantially the center thereof to form cut pile yarn ends of equal height.
Inventors:
Application Number:
05/145195
Publication Date:
05/01/1973
Filing Date:
05/20/1971
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Export Citation:
Primary Class:
Other Classes:
112/80.550
International Classes:
D05C15/22; D05C15/24; D05C15/00
Field of Search:
112/79R,79A,80,266,410
US Patent References:
| 3138126 | Apparatus for tufting high and low cut pile | June 1964 | Card |
Primary Examiner:
Boler, James R.
Claims:
What is claimed is
1. A tufting machine comprising:
2. The invention according to claim 1 in which said hook and spreader element have bottom edges in substantially the same horizontal plane, the thickness of said solid hook being substantially equal to the distance between said cutting surface and the opposite side of said spreader element from said hook.
3. The invention according to claim 1 in which said stitching means comprises a needle, means for reciprocably moving said needle through the fabric on said opposite side of said hook.
1. A tufting machine comprising:
2. The invention according to claim 1 in which said hook and spreader element have bottom edges in substantially the same horizontal plane, the thickness of said solid hook being substantially equal to the distance between said cutting surface and the opposite side of said spreader element from said hook.
3. The invention according to claim 1 in which said stitching means comprises a needle, means for reciprocably moving said needle through the fabric on said opposite side of said hook.
Description:
BACKGROUND OF THE INVENTION
This invention relates to a tufting machine, and more particularly to a cut pile looper mechanism for a tufting machine.
Traditionally, cut pile has been produced in tufting machines by a reciprocable looper or hook engaging and holding a loop of yarn carried through a base fabric by a reciprocable needle, and a reciprocable knife cooperating with one side of the looper to cut the loop of yarn into two separate yarn ends or strands. As the knife reciprocates along and against one side of the looper, the yarn loop is cut on one side of the hook to form two unequal cut pile strands or ends. Such cutting is referred to in the industry as a "J-CUT", because the long strand is J-shaped, or because the unequal strands of the yarn segment stitched in the base fabric is J-shaped. Many manufacturers of cut pile fabrics, particularly carpets, have found the conventional "J-CUT" pile to be objectionable because of the unequal height of the pairs of strands in each cut loop, which presents an uneven pile surface.
Applicants have attempted to remedy this problem by cutting the loop held by a cut pile hook on opposite sides of the hook in two places at uniform depths, as described in their U.S. Pat. No. 3,662,697, issued May 16, 1972, for "METHOD AND APPARATUS FOR TUFTING UNIFORM CUT PILE".
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide a method and apparatus in the form of a novel looper mechanism including a looper element or hook, a spreader element and a knife member for cutting the loop yarns evenly and in the center thereof to form cut strands or yarn ends in each loop of equal height.
This invention contemplates a looper mechanism for a multiple-needle tufting machine incorporating looper elements or hooks, and a spreader element and knife member cooperating with each of the hooks. The spreader element is associated with each hook so that both the hook and the spreader element enter the loop to spread it and hold it taut while the knife member is reciprocated between the hook and spreader element to cut the loop substantially in the center thereof.
The spreader element is preferably fixed to the hook so that it extends along and in the same direction as the bill of the hook and has a free end which is closely adjacent to, and preferably biased against, the hook adjacent its free end. The middle portion of the spreader element is preferably spaced apart laterally from the side of the hook bill, not only to spread the loop, but also to provide a space for receiving the reciprocal knife as it cuts the bottom portion of the spread loop in its center thereof.
This invention is an improvement over the looper and cutting mechanism disclosed in applicants' above U.S. Pat. No. 3,662,697, in that, in this invention, the loop is cut only once in the center thereof. In U.S. Pat. No. 3,662,697, the loop was cut in two places at equal depths, so that the cut-out yarn portion was wasted.
Another advantage of this invention is that the spreader element and hook hold the bottom portion of the loop in a substantially horizontal taut position so that the knife cuts substantially transversely of the yarn to make a smooth straight cut, as opposed to the angular cut which the knife makes through a loop held on the side of a hook in a conventional cut pile tufting mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary sectional elevation of a portion of a tufting machine incorporating this invention, disclosing the looper mechanism in a cutting position;
FIG. 2 is a fragmentary view similar to FIG. 1 disclosing the looper mechanism in its noncutting, or loop forming, position;
FIG. 3 is a front-end elevation of the looper and spreader element made in accordance with this invention, as viewed along the line 3--3 of FIG. 1;
FIG. 4 is a top-plan view of the looper and spreader element disclosed in FIG. 3, and further disclosing, fragmentarily, a knife member and a loop in cutting position;
FIG. 5 is a section taken along the line 5--5 of FIG. 2; and
FIG. 6 is a section taken along the line 6--6 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in more detail, FIG. 1 discloses a typical needle bar 10 supporting a plurality of needles 11 (only one of which is shown in the drawings) disposed in a row transversely of the tufting machine. The needle 11 are adapted to be reciprocably moved between their lower position disclosed in FIG. 2 and their upper position disclosed in FIG. 1 by a push rod 12 driven by conventional means, not shown.
Supported upon a needle plate 13 for movement longitudinally from front to rear, in the direction of the arrow, through the tufting machine is a base fabric 15. Each needle 11 carries a yarn 16 through the base fabric 15 upon each stroke of the needle 11.
The looper mechanism made in accordance with this invention includes a plurality of looper elements or cut pile hooks 18 mounted transversely of the tufting machine upon the same gauge as the needles 11 in a hook bar 19. The hook bar 19 is supported upon the hook shaft, not shown, for reciprocal movement, by means, not shown, in a conventional manner.
The looper element or cut pile hook 18 includes a bill 22 having a free end 23, and a throat 24 opposite the free end 23.
A spreader element 25, which is disclosed in the drawings in the form of a spring clip, has an arcuately pointed free end 26 and an opposite fixed end or base portion 27. As best disclosed in FIG. 4, the intermediate blade portion 28 is laterally spaced from the opposing face of the bill 22 of the hook 18. However, the blade portion 28 converges toward the free end 26 so that the free end 26 is very close to, or preferably touching or engaging, the bill 22 adjacent the free end 23 of the hook. The spreader element 25 is preferably of integral construction and a uniform material, such as spring steel. The fixed end or base portion 27 is preferably flat, so that it fits flush against the side of the hook 18, and is fixed in place by securing means such as bolts 29.
When fixed in place, the spring material of the spreader element 25 biases the free end 26 against the side of the bill 22, so that when the free ends 23 and 26 are inserted within a loop, such as 30, both the bill 22 and the blade 28 will fit within the loop to spread it, as best disclosed in FIGS. 5 and 6. As the bill 22 and spreader blade portion 28 progressively move through the loop 30, the loop is spread apart because of the gradual rearward divergence between the bill 22 and the spreader blade portion 28, to a taut spreading position, such as that disclosed in FIG. 5.
The looper mechanism made in accordance with this invention also includes a conventional tufting knife 32 mounted in knife block or holder 33 which is fixed to the transverse knife shaft 34. The knife shaft 34 is adapted to be reciprocated in synchronism with the hook bar 19, by means, not shown, in a conventional manner. The knife 32 is reciprocated between its non-cutting position disclosed in FIG. 2 and its cutting position disclosed in FIG. 1. The knife 32 is flexed in a conventional manner, as best disclosed in FIGS. 5 and 6 so that it is tensioned flush against the opposing side of the tufting hook 18 to provide a close-fitting scissors action in cutting the loop 30.
Also as best disclosed in FIGS. 5 and 6, the knife 32 is adapted to reciprocate upward into a cutting position between the bill 22 and the spreader blade 28. The relative thicknesses of the bill 22 and the spreader blade 28, as well as the spacing between the bill 22 and the spreader blade 28, are such, that the knife 32 will cut the spread, taut, bottom bight portion 36 (FIG. 5) of the loop 30 very close to the center of the bight portion 36 to produce severed cut pile strands 39 and 40 of equal lengths (FIG. 6).
In order for the cut to be made in the center of the loop 30, the center of the bight portion 36 should be aligned with the side face of the bill 22 of the hook 18, opposing the spreader blade 28. Also, the bottom portion of the spreader blade 28 should be laterally spaced from the bottom portion of the bill 22 in a plane substantially parallel to the base fabric 15. Furthermore, the spacing between the cutting face of the bill 22 and the outer face of the spreader blade 28 engaged by the loop 30 should be approximately equal to the thickness of the bill 22.
Of course, the spreader blade 28 could be above its disclosed position, that is raised in relation to the hook bill 22, so long as the center of the loop 30 is maintained in cutting alignment with the knife 32 cooperating with the cutting face of the bill 22. However, another advantage of having the blade 28 in substantially direct lateral spaced relationship with the bill 22, that is, the bottom edges of the blade 28 and bill 22 being in the plane parallel to the base fabric 15, is that the knife cuts square or transversely across the yarn in the bight portion 36 to make a smooth straight cut. A square cut of the loop 30 provides tuft pile strands 39 and 40 having their ends presenting a smoother and more attractive appearance, in a tufted cut pile carpet, for example. A square cut in the tufted yarn strands is much superior to the jagged-looking angular cuts normally encountered in conventional cut pile tufting.
In the operation of the invention, the mechanism for reciprocating the push rod 12, hook bar 18 and knife shaft 34, and for moving the base fabric 15 in the direction of the arrow, are the same as in any conventional tufting machine. Thus, in FIG. 2 the needle 11 has been moved to its lowermost position for carrying the yarn 16 through the base fabric 15, and the cut pile hook 18, spreader element 25 and tufting knife 32 have been moved to their forwardmost position. In the forwardmost position, the bill 22 of hook 18 and blade 28 of the spreader element 25 have been extended across the needle 11 to catch, engage and hold a loop of yarn 30. It will be noted, particularly in FIG. 2, that the spreader element 25 is on the opposite side of the tufting hook 18 from the needle 11, in order to facilitate the spreader blade 28 and bill 22 together projecting through the loop 30. The loops 30 are progressively moved toward the throat of the hook 18, for each reciprocal movement of the hook bar 19. Of course, in the forwardmost position, the knife 32 is in its lowermost, non-cutting, position.
In the other extreme or rearmost reciprocal position, as best disclosed in FIG. 1, the each needle 11 is elevated above the base fabric 15, the cut pile hook 18 reciprocates rearward holding the spread loops 30 upon the bill 22 and the spreader blade 28, as the base fabric 15 moves rearward. Knife 32 also reciprocates rearward, but moves upward relative to the cut pile hook 18 so that its upper cutting edge moves above the lower edge of the bill 22 and between the bill 22 and the spreader blade 28, as best disclosed in FIGS. 1 and 6, to sever the rearmost loop 30 in the center of the bight portion 36.
As the knife 32 moves upward between the bill 22 and spreader blade 28, the knife 32 may actually engage and spread the spreader blade 28 away from the bill 22, or the spacing between the blade 28 and bill 22 may be great enough that no spreading of the spreader blade 28 will be effected. Whether the spreader blade 28 is laterally moved away or not by the knife 32 is immaterial to the functioning of the device. If the blade 28 is spread away, then the free end 26 will spread away from the free end 23 of the hook 18. The spread free ends, in the rearwardmost position of the hook 18 as disclosed in FIG. 1, will not affect the function of the machine, so long as the free ends 23 and 26 return toward and engage each other when the looper 18 is in its forwardmost position, as disclosed in FIG. 2, for picking up the next loop 30 from the needle 11.
By the same token, it is not even necessary that the spreader element 25 be made of a spring material, so long as the spacing between the bill 22 and spreader blade 28 is sufficient to permit the knife blade 32 to rise and cut the loop 30 in the center, and so long as the free end 26 of the spreader element 25 and the free end 23 of the hook 18 are close enough, as they move forward, that they will enter the loop 30 without snagging upon or being separated by the yarn loop 30.
This invention relates to a tufting machine, and more particularly to a cut pile looper mechanism for a tufting machine.
Traditionally, cut pile has been produced in tufting machines by a reciprocable looper or hook engaging and holding a loop of yarn carried through a base fabric by a reciprocable needle, and a reciprocable knife cooperating with one side of the looper to cut the loop of yarn into two separate yarn ends or strands. As the knife reciprocates along and against one side of the looper, the yarn loop is cut on one side of the hook to form two unequal cut pile strands or ends. Such cutting is referred to in the industry as a "J-CUT", because the long strand is J-shaped, or because the unequal strands of the yarn segment stitched in the base fabric is J-shaped. Many manufacturers of cut pile fabrics, particularly carpets, have found the conventional "J-CUT" pile to be objectionable because of the unequal height of the pairs of strands in each cut loop, which presents an uneven pile surface.
Applicants have attempted to remedy this problem by cutting the loop held by a cut pile hook on opposite sides of the hook in two places at uniform depths, as described in their U.S. Pat. No. 3,662,697, issued May 16, 1972, for "METHOD AND APPARATUS FOR TUFTING UNIFORM CUT PILE".
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide a method and apparatus in the form of a novel looper mechanism including a looper element or hook, a spreader element and a knife member for cutting the loop yarns evenly and in the center thereof to form cut strands or yarn ends in each loop of equal height.
This invention contemplates a looper mechanism for a multiple-needle tufting machine incorporating looper elements or hooks, and a spreader element and knife member cooperating with each of the hooks. The spreader element is associated with each hook so that both the hook and the spreader element enter the loop to spread it and hold it taut while the knife member is reciprocated between the hook and spreader element to cut the loop substantially in the center thereof.
The spreader element is preferably fixed to the hook so that it extends along and in the same direction as the bill of the hook and has a free end which is closely adjacent to, and preferably biased against, the hook adjacent its free end. The middle portion of the spreader element is preferably spaced apart laterally from the side of the hook bill, not only to spread the loop, but also to provide a space for receiving the reciprocal knife as it cuts the bottom portion of the spread loop in its center thereof.
This invention is an improvement over the looper and cutting mechanism disclosed in applicants' above U.S. Pat. No. 3,662,697, in that, in this invention, the loop is cut only once in the center thereof. In U.S. Pat. No. 3,662,697, the loop was cut in two places at equal depths, so that the cut-out yarn portion was wasted.
Another advantage of this invention is that the spreader element and hook hold the bottom portion of the loop in a substantially horizontal taut position so that the knife cuts substantially transversely of the yarn to make a smooth straight cut, as opposed to the angular cut which the knife makes through a loop held on the side of a hook in a conventional cut pile tufting mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary sectional elevation of a portion of a tufting machine incorporating this invention, disclosing the looper mechanism in a cutting position;
FIG. 2 is a fragmentary view similar to FIG. 1 disclosing the looper mechanism in its noncutting, or loop forming, position;
FIG. 3 is a front-end elevation of the looper and spreader element made in accordance with this invention, as viewed along the line 3--3 of FIG. 1;
FIG. 4 is a top-plan view of the looper and spreader element disclosed in FIG. 3, and further disclosing, fragmentarily, a knife member and a loop in cutting position;
FIG. 5 is a section taken along the line 5--5 of FIG. 2; and
FIG. 6 is a section taken along the line 6--6 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings in more detail, FIG. 1 discloses a typical needle bar 10 supporting a plurality of needles 11 (only one of which is shown in the drawings) disposed in a row transversely of the tufting machine. The needle 11 are adapted to be reciprocably moved between their lower position disclosed in FIG. 2 and their upper position disclosed in FIG. 1 by a push rod 12 driven by conventional means, not shown.
Supported upon a needle plate 13 for movement longitudinally from front to rear, in the direction of the arrow, through the tufting machine is a base fabric 15. Each needle 11 carries a yarn 16 through the base fabric 15 upon each stroke of the needle 11.
The looper mechanism made in accordance with this invention includes a plurality of looper elements or cut pile hooks 18 mounted transversely of the tufting machine upon the same gauge as the needles 11 in a hook bar 19. The hook bar 19 is supported upon the hook shaft, not shown, for reciprocal movement, by means, not shown, in a conventional manner.
The looper element or cut pile hook 18 includes a bill 22 having a free end 23, and a throat 24 opposite the free end 23.
A spreader element 25, which is disclosed in the drawings in the form of a spring clip, has an arcuately pointed free end 26 and an opposite fixed end or base portion 27. As best disclosed in FIG. 4, the intermediate blade portion 28 is laterally spaced from the opposing face of the bill 22 of the hook 18. However, the blade portion 28 converges toward the free end 26 so that the free end 26 is very close to, or preferably touching or engaging, the bill 22 adjacent the free end 23 of the hook. The spreader element 25 is preferably of integral construction and a uniform material, such as spring steel. The fixed end or base portion 27 is preferably flat, so that it fits flush against the side of the hook 18, and is fixed in place by securing means such as bolts 29.
When fixed in place, the spring material of the spreader element 25 biases the free end 26 against the side of the bill 22, so that when the free ends 23 and 26 are inserted within a loop, such as 30, both the bill 22 and the blade 28 will fit within the loop to spread it, as best disclosed in FIGS. 5 and 6. As the bill 22 and spreader blade portion 28 progressively move through the loop 30, the loop is spread apart because of the gradual rearward divergence between the bill 22 and the spreader blade portion 28, to a taut spreading position, such as that disclosed in FIG. 5.
The looper mechanism made in accordance with this invention also includes a conventional tufting knife 32 mounted in knife block or holder 33 which is fixed to the transverse knife shaft 34. The knife shaft 34 is adapted to be reciprocated in synchronism with the hook bar 19, by means, not shown, in a conventional manner. The knife 32 is reciprocated between its non-cutting position disclosed in FIG. 2 and its cutting position disclosed in FIG. 1. The knife 32 is flexed in a conventional manner, as best disclosed in FIGS. 5 and 6 so that it is tensioned flush against the opposing side of the tufting hook 18 to provide a close-fitting scissors action in cutting the loop 30.
Also as best disclosed in FIGS. 5 and 6, the knife 32 is adapted to reciprocate upward into a cutting position between the bill 22 and the spreader blade 28. The relative thicknesses of the bill 22 and the spreader blade 28, as well as the spacing between the bill 22 and the spreader blade 28, are such, that the knife 32 will cut the spread, taut, bottom bight portion 36 (FIG. 5) of the loop 30 very close to the center of the bight portion 36 to produce severed cut pile strands 39 and 40 of equal lengths (FIG. 6).
In order for the cut to be made in the center of the loop 30, the center of the bight portion 36 should be aligned with the side face of the bill 22 of the hook 18, opposing the spreader blade 28. Also, the bottom portion of the spreader blade 28 should be laterally spaced from the bottom portion of the bill 22 in a plane substantially parallel to the base fabric 15. Furthermore, the spacing between the cutting face of the bill 22 and the outer face of the spreader blade 28 engaged by the loop 30 should be approximately equal to the thickness of the bill 22.
Of course, the spreader blade 28 could be above its disclosed position, that is raised in relation to the hook bill 22, so long as the center of the loop 30 is maintained in cutting alignment with the knife 32 cooperating with the cutting face of the bill 22. However, another advantage of having the blade 28 in substantially direct lateral spaced relationship with the bill 22, that is, the bottom edges of the blade 28 and bill 22 being in the plane parallel to the base fabric 15, is that the knife cuts square or transversely across the yarn in the bight portion 36 to make a smooth straight cut. A square cut of the loop 30 provides tuft pile strands 39 and 40 having their ends presenting a smoother and more attractive appearance, in a tufted cut pile carpet, for example. A square cut in the tufted yarn strands is much superior to the jagged-looking angular cuts normally encountered in conventional cut pile tufting.
In the operation of the invention, the mechanism for reciprocating the push rod 12, hook bar 18 and knife shaft 34, and for moving the base fabric 15 in the direction of the arrow, are the same as in any conventional tufting machine. Thus, in FIG. 2 the needle 11 has been moved to its lowermost position for carrying the yarn 16 through the base fabric 15, and the cut pile hook 18, spreader element 25 and tufting knife 32 have been moved to their forwardmost position. In the forwardmost position, the bill 22 of hook 18 and blade 28 of the spreader element 25 have been extended across the needle 11 to catch, engage and hold a loop of yarn 30. It will be noted, particularly in FIG. 2, that the spreader element 25 is on the opposite side of the tufting hook 18 from the needle 11, in order to facilitate the spreader blade 28 and bill 22 together projecting through the loop 30. The loops 30 are progressively moved toward the throat of the hook 18, for each reciprocal movement of the hook bar 19. Of course, in the forwardmost position, the knife 32 is in its lowermost, non-cutting, position.
In the other extreme or rearmost reciprocal position, as best disclosed in FIG. 1, the each needle 11 is elevated above the base fabric 15, the cut pile hook 18 reciprocates rearward holding the spread loops 30 upon the bill 22 and the spreader blade 28, as the base fabric 15 moves rearward. Knife 32 also reciprocates rearward, but moves upward relative to the cut pile hook 18 so that its upper cutting edge moves above the lower edge of the bill 22 and between the bill 22 and the spreader blade 28, as best disclosed in FIGS. 1 and 6, to sever the rearmost loop 30 in the center of the bight portion 36.
As the knife 32 moves upward between the bill 22 and spreader blade 28, the knife 32 may actually engage and spread the spreader blade 28 away from the bill 22, or the spacing between the blade 28 and bill 22 may be great enough that no spreading of the spreader blade 28 will be effected. Whether the spreader blade 28 is laterally moved away or not by the knife 32 is immaterial to the functioning of the device. If the blade 28 is spread away, then the free end 26 will spread away from the free end 23 of the hook 18. The spread free ends, in the rearwardmost position of the hook 18 as disclosed in FIG. 1, will not affect the function of the machine, so long as the free ends 23 and 26 return toward and engage each other when the looper 18 is in its forwardmost position, as disclosed in FIG. 2, for picking up the next loop 30 from the needle 11.
By the same token, it is not even necessary that the spreader element 25 be made of a spring material, so long as the spacing between the bill 22 and spreader blade 28 is sufficient to permit the knife blade 32 to rise and cut the loop 30 in the center, and so long as the free end 26 of the spreader element 25 and the free end 23 of the hook 18 are close enough, as they move forward, that they will enter the loop 30 without snagging upon or being separated by the yarn loop 30.